查询词典 abnormal curvature

Some properties of inversions are proved, It indicates that the inversion is conformal, the image of line of curvature is still the line of curvature of the inversion S of the hypersurface S, the principal curvature, the total curvature, and mean curvature of S are the functions...

在n-1维超曲面的反图变换中，示明反图变换为保角表示法，曲率线系的反影仍为反超曲面的曲率线系，反超曲面的主曲率，全曲率与平均曲率为原超曲面的主曲率的函数等。 3。最后导出公式(1)在四维空间与通常空间之特殊形式

In this paper, we will study the definination of lines of curvature and the correlative conception, for example, normal curvature, principal direction and principal curvature and so on, the connection of lines of curvature and correlative conception, especially probe into the solution with the equation of lines of curvature and the equivalence with its determinant theorem.

本课题主要研究曲率线的定义及其相关概念如法曲率、主方向、主曲率等，曲率线与相关概念的关系，重点探讨了曲率线方程的求解及曲率线判定的等价定理。

Results: 1. The depression patients in neuroendocrine abnormity make up 59.4% of the total. 2. Correlation of clinical features and neuroendocrine diversity of depression patients.① Agitate symptom often existed in HPA axle abnormal group.② The weight diversity was not obvious suffered HPT axle abnormal depression frequently, Sleep disorder and anxiety often exist in HPT axle abnormal group.③ Elder women suffered HPG axle abnormal depression frequently, The symptom of somatic often exist in HPG axle abnormal group.④ Self-reproach and delay symptom often existed in the HPA axle and HPT axle abnormal group.⑤ The adolescent fuffered the normal neuroendocrine group, Patients of the normal neuroendocrine group were often combined with anhedonia.

结果显示：⒈抑郁症患者神经内分泌异常率达到 59.4%；⒉抑郁症患者临床特征与不同神经内分泌轴具有相关性以下几点值得注意；① HPA 轴异常组抑郁症患者多伴有激越症状；② HPT 轴异常组抑郁症患者体重改变不明显，多伴有睡眠障碍、迟纯症状和焦虑症状，常出现自杀观念；③ HPG 轴异常组抑郁症患者多发于年龄偏大的女性，躯体症状多明显；④ HPA 轴和 HPT 轴均异常组抑郁症患者多伴有体重减轻和明显自责和迟滞症状；⑤正常组抑郁症患者多发于青少年，快感缺失症状明显。

The incidence of major abnormal ECG were 7.3% for STT changes, 5.6% for sinus tachycardia, 4.4% for sinus arrhythmia, 3.4% for ventricular premature beats, 2.0% for bundle branch block and 1.8% for atrial premature beats; Apart from preexcitation syndrome, the incidence of abnormal ECG for male was higher than that of female;Most of abnormal ECG increased with age. A few abnormal ECG such as sinus tachycardia, sinus arrhythmia, sick sinus syndrome decreased with age. The incidence of sinus bradycardia and preexcitation syndrome were bail shape with age. Half of abnormal ECG adults had at least two abnormal ECG, such as STT changes combined with ventricular premature beats or bundle branch block.

异常心电图较多的有STT改变（7.3%）、窦性心动过速（5.6%）、窦性心律不齐（4.4%）、室性早搏（3.4%）、束支传导阻滞（2.0%）、房性早搏（1.8%）；除预激综合征外，其他异常心电图都是男性多于女性；多数异常心电图的检出率随年龄增加而增加，但窦性心动过速、窦性心律不齐、病窦综合征随年龄增加而减少，窦性心动过缓和预激综合征的检出率与年龄呈&杓形&关系；在异常心电图人群中，有约1/2的人合并2种或2种以上的心电图改变，最常见的是缺血性STT改变合并室性早搏或传导阻滞。

The effect of tribology factors on bearing vibration is studied experimentally. AR model and WPT are used to processing the normal arid abnormal signals. The results are as follows:1. The vibration of ball bearings is caused by the tribology action of contact pairs of ball and ring races and has the essential of tribo-dynamics. Any factors affecting the tribology characteristics of contact pairs will affect vibration and noise of bearings consequently.2. Vibration characteristics of bearing keep almostly unchanged with the increasing of axial load expecting the increasing of nature frequencies. When radial load increasing with axial load unchanged, nature frequencies keep unchanged but some new vibration peaks appears in the spectrum.3. Vibration amplitudes are damped and nature frequency are enhanced with sufficient lubrication. Vibration and noise of bearings increase obviously and roar can happen and the contact surfaces scratch slightly under insufficient and unclean lubrication state. Bearing will be disabled in a few minutes without any lubrication.4. Bearing vibration is unstable under low speed. With the speed increasing, the vibration become stable and natural frequencies increase slightly but the amplitudes increase apparently.5. Bearing vibration can be excited only by some harmonics ofwaviness without lubrication and by all harmonics with lubrication based on the theoretical analysis.6. The nature frequencies of ball bearings decrease with the increasing sizes. When international clearance increasing, nature frequencies decrease in radial and increase in axial and angular and the amplitudes increase in radial and decrease in axial and angular. When the number of balls increasing, nature frequencies increase and amplitudes decrease. When the pitch diameter increasing, axial nature frequency increase and others nearly keep no change. When outer race groove curvature radius increasing, nature frequencies increase in radial and decrease in axial and angular and amplitudes keep no change in radial and increase in axial and angular. When inner race groove curvature radius increasing, nature frequencies decrease and amplitudes increase.7. The distortion in amplitude and frequency components of bearing vibration signals picked up by the present probe measurement method is founded and right conclusions cannot be achieved by the signals. When accelerometer is rigidly screwed with steel stud onto a flat outer surface of a ball bearing, vibration signal can be got without distortion and the reliability of research on bearing vibration is assured.8. AR model is suitable for large samples of bearing vibration signals, square root of length of samples can be used as the upper limitation of order determination and the FPE order selection criterion is effective. Many advantages of AR spectrum are founded over the classical based on FFT.9. Time-Frequency analysis is necessary for abnormal noise of ball bearings. WPT overcomes the principle shortcomings of STFT and proved to be a best tool to process the abnormal signals.

理论分析和试验研究表明： 1球轴承振动是钢球—滚道接触副中的各种摩擦学作用引起的，具有摩擦动力学的本质，任何对接触副的摩擦学特性有影响的因素都将对球轴承的振动和噪声特性产生影响； 2中心轴向载荷作用下，载荷增大使球轴承的固有振动频率升高，载荷越大同样的载荷增幅引起的频率升幅减小，足够大的中心轴向载荷作用下载荷的变化对球轴承振动的频率特性不会产生明显的影响； 3轴向和径向联合载荷作用下，径向载荷不大时球轴承振动的固有频率基本不变，但是可能引起变刚度激励的非线性振动，出现新的频峰，过大的径向载荷将使部分钢球脱离接触，使球轴承的振动和噪声呈现不稳定状态； 4润滑对球轴承的振动和噪声特性有重要的影响，良好的润滑对振动有明显的抑制作用，润滑不充分时，振动和噪声的水平会有明显增高，一定条件下还会激发接触副中的谐振，发出啸声，造成接触表面的伤害，无润滑干接触时，短时的运转就会损伤接触副表面，使振动和噪声迅速增大，并随时可能引发严重的磨损和卡滞失效；接触副润滑良好时，油膜的"刚化效应"使球轴承振动的固有频率有所提高，润滑剂中含有弥散性污浊时，振动的幅度总体升高，但弥散性污浊不会改变球轴承振动的频率特性；浙江大学博士学位论文：球轴承振动的研究 5低速时，球轴承振动的基本特征呈现不稳定状态，随着转速的提高，球轴承振动的频率特性趋于稳定，固有频率频峰升高； 6理论分析表明，干接触时钢球和滚道表面波纹度的某些谐波分量能激励球轴承的振动，振动的幅值与谐波幅值成正比，实际球轴承中钢球的分布不可能完全均匀，波纹度的激励作用会随时发生；润滑接触的分析表明，波纹度的任意谐波分量均能激励球轴承的振动； 7球轴承的几何和结构参数分析表明，球轴承尺寸越大，径向、轴向和角振动的固有频率越低；钢球中心圆直径增大，球轴承的径向和轴向振动的固有频率基本不变，角振动的固有频率有所上升，振动的幅频特性基本不变；径向游隙加大使球轴承的径向振动固有频率降低，轴向和角振动的固有频率有所升高，径向振动幅频特性的幅值升高，而轴向和角向降低；钢球的数量增多使球轴承振动的固有频率上升，幅频特性的幅值下降，径向振动的幅值下降最为明显；外圈沟曲率半径系数增大使球轴承径向振动的固有频率升高，轴向和角振动的固有频率降低，径向幅频特性基本不变，轴向和角向幅频特性幅值升高；内圈沟曲率半径系数增大使径向、轴向和角振动固有频率均下降，振动幅频特性的幅值均有升高； 8试验对比表明，传感器采用探针式安装时，由于探针接触副接触特性的影响，钡(量得到的球轴承振动信号有失真，采用专门设计和制作的试验球轴承，以固定式安装加速度计，首次测量得到了球轴承振动的真实信号，通过对振动信号的分析，验证了球轴承振动的理论模型； 9)基于时间序列分析的AR模型适用于大样本球轴承振动信号的分析，以样本长度的均方根值作定阶上界，FPE做判阶准则，给出的AR谱光滑，频率分辨率高，是球轴承振动分析的简便而可靠的手段； 10以时频域分析的小波包变换分析球轴承异音信号能够比较好地定位和聚焦异音发生的时间，时间间隔，频率范围，同样是球轴承振动分析的可靠的手段，可用作球轴承故障诊断技术。

This paper reported a new method using tangential curvature to establish a mathematical model of the anterior cornea and an analysis of the regularity of the distribution of the asphericity Q. The curvature in the horizontal meridians is a prolate ellipse. The curvature in the vertical meridians is an oblate ellipse. The curvature of the horizontal meridians is important for anterior corneal asphericity.

本研究分析了运用正切曲率半径值建立人眼前表面角膜数学模型的科学性，显示角膜前表面水平子午线方向非球面性趋向于长椭圆，垂直子午线方向非球面性趋向于扁椭圆，说明人眼角膜的非球面性特性主要由水平子午线实现。

In addition, we made account for the selection of inverted bending curvature of pipe axis and the length of equal curvature region, and pointed out that we can only equalize the curvature in the equal region and carrying out straightening really is in the region of unequal curvature. This is the development and perfect of bending straightening theory and this method can spread to bar straightening machine.

此外，还对反弯曲线曲率和等曲率区长度的选取作了说明，指出在等曲率弯曲区只能使曲率均匀化，而真正实现矫正是在后部的非等曲率弯曲区，这是对矫正理论的深入和完善，并且这一研究方法也可推广到棒材矫正机。

The paper deals with curvature line and curvature characteristic of developable surface based on differential invariant of developable surface and it details curvature line and curvature characteristic of cone and tangent surface .

本文通过可展曲面的微分不变量，导出可展面的曲率线与曲率特征，并以锥面和切线曲面为例阐明这些特性的几何意义。

Chapter 2 introduces some propaedeutics of classic differential geometry, which include the first basic form, the second basic form, normal curvature, main curvature, mean curvature, Gauss curvature, unit normal vector, main vector, etc.

第二章介绍一系列的预备知识，主要是关于古典微分几何中第一，第二基本形式的定义，法曲率，主曲率，平均曲率，Gauss曲率，单位法向量，主方向等的定义。

In this paper, a "rigid bar relative movement model" was established to illustrate the traces of the helices in wire ropes. The angular speed of a moving particle of the model was relatives to curvature tensor to derive the curvature components and torsion of helices in multi-layer wire ropes. According to long and thin rod theory of Love and Yen-Chen's theoretical model considered the contact force and frictional force, the force-deformation or force-strain relative of wire in curved wire ropes subjected axial force is derived from the curvature components and curvature increment.

本研究改以刚杆相对运动模型，直接描述钢索中钢绞线轨迹，并且透过角速度类比曲率张量之概念，推导圆弧型多层钢索内部之钢铰线之曲率分量与扭率；之后再依据Love的细长杆理论，辅以Yen-Chen在考虑接触力及摩擦力下所修正之理论模型，以曲率及曲率增量来探讨圆弧型钢索受静态荷重作用下，钢绞线之受力与变形或应变关系。

I'm going tor her!

我这就去救她！

As rise are design to help keep a several toney , a brain chemical at continues lever.

SSRI被设计来帮助保持血液中的复合胺即在大脑中一个连续水平的化学物质。